package org.bridgen.test.compare;

/**
 * 
 * @author Emma Söderberg <emma add cs.lth.se>
 *
 */

public interface CostFunction {

	/* Required by Lemma 1 */

	// µ(l_1[i],empty)
	public int cost(Label l1, Label.Empty empty);

	// µ(empty,l_2[j])
	public int cost(Label.Empty empty, Label l2);

	
	/* Required by Lemma 2 */
	
	// µ(l_1[i],L_2[j])
	public int cost(Label l1, Label l2);
}
